1. Field of the Invention
This invention relates to a cutting tool that can be realized in particular in the form of a rotary tool with a tool shank which acts as a support for a cutting insert in the form of a perforated plate, in particular a disposable perforated plate, and with a feed device as a means of adjustment for the positioning of the perforated plate on the tool shank. Stress applied by a simple screw is increasingly being used to fasten perforated plates of this type, in particular disposable perforated plates. In this case, the screw is used to fasten the perforated plate to the tool shank. The precise positioning of the perforated plate on the tool shank is thereby effected by adjustment means that apply pressure to the lateral contact surface of the perforated plate, which generates a position offset between the threaded hole and the screw head of the fastening screw. An adjustment means of this type is described in DE 197 17 741 A1, for example.
2. Background Information
An adjustable fixation of a perforated plate to the base body of the tool or tool shank at approximately a right angle to the axis of the hole can of course be realized economically. However, the tolerances between the contact surfaces and the threaded hole must be kept within narrow limits, so that the screw is not overloaded during the feed operation. On the other hand, the tolerances of the width of the perforated plate and the position of the contact surfaces in the plate seat of the tool shank limit the machining tolerances of the cutting tool, which means that on a boring tool in particular, the boring tolerance is likewise limited.
The development of cutting technology requires ever closer drilling tolerances. However, tool developments toward this objective can only be combined to a limited extent with the advantages of the screw bracing of a perforated plate. As the feed travel increases, the screw is subjected to an increasing bending load. This bending load represents a safety risk that can cause not only damage to the tool, the workpiece and the machine, but can also pose a threat to the operating personnel. EP 0 552 774 B1 describes, as one solution, a sled-like mounting of perforated plates on the tool shank with any desired feed travel. However, this solution weakens the substructure of the perforated plate seat and deforms the substructure when the perforated plate is braced.